Methods: :
Two series of anterior segment optical images of 11 eyes of10 subjects were collected with the Galilei Dual ScheimpflugAnalyer (Ziemer Group) of normal eyes under the condition ofnormal alignment and repeated with a calibrated 1-mm horizontalmisalignment. The average central anterior curvatures over thecentral 4 mm diameter zone were recorded for the following conditions:normal manual alignment and not re-centered to pupil (C-ncp),normal manual alignment and re-centered to pupil (C-cp), calibrateddecentration and not centered to pupil (D-ncp), and calibrateddecentered and re-centered to pupil (D-cp). The conditions C-ncpvs C-cp, D-ncp vs D-cp, and C-cp vs D-cp were statisticallycompared with t-tests. A Bonferroni correction for multiplecomparisons was used to set the significance threshold a prioriat p<0.017.

Conclusions: :
Recentration of topographic curvature calculations to the pupilcenter provides a consistent approach to evaluation of centraltopographic parameters, even under conditions of misalignment.Pupil re-centration may provide an advantage in comparing topographicmaps acquired under varying circumstances.